Improvement in pumps for deep wells



IJNITED STATES PATENT OFFICE,

BENJAMIN CRAWFORD, OF ALLEGHENY, PENNSYLVANIA.

IMPROVEMENT IN PUMPS FOR DEEP WELLS.

Specification forming part of Letters Patent No, 56,380, dated July 17,1866.

To all whom it may concern:

Be it known that I, BENJAMIN CRAWFORD, of the city of Allegheny, in thecounty of Allegheny and State of Pennsylvania, have i11- vcnted a newand useful Improvement in Pumps for Artesian lVells and I do herebydeclare the following to be a full, clear, and exact descriptionthereof, reference being bad to the accompanying drawings, forming partof this specification, in which- Figure l is an external elevation of myimproved pump. Fig. 2 is a vertical section of the pump, the plane ofsection being at right angles to the plane of elevation of Fig. I.

In both figures like letters of reference are employed to designatesimilar parts.

The pump, which I am about to describe being designed for use inArtesian wells, the tubing above the working valves is made of anyrequired length.

In Artesian wells, especially in those from which petroleum is obtained,great inconvenience is experienced from the presence of gas in the well,which exerts more or less upward pressure, and frequently interferesmaterially with the pumping of the oil and water. Owing to the longcolumn of water or oil in the rising-pipe of the pump above the valves,there is so powerful a downward pressure that the gas cannot rise freelyto the top of the well, and, with a pump of ordinary construction, willfill the working barrel of the pump between the two valves, and thuseffectually stop the operation of raising the oil and water. It willalso raise the lower valve during the downward stroke of thepump-piston, and allow the oil and water to flow back again into thewell. Thus, whenever the pressure of gas in the well is not sufficientto force the oil and water up through the rising-pipe to the top of thewell and cause it to flow without pumpin g, it will obstruct the actionof the pump, and often render it entirely inoperative, unless it can begot rid of without being permitted to pass through the column of liquidin the well-tube above the pump-valves.

My invention is designed to overcome these difficulties and secure theproper action of the pump, notwithstanding the upward pressure To enableothers skilled in the art to make use of my invention, I will proceed todescribe the construction and operation of myimproved pump, and in sodoing I will first explain those parts which relate to the raising ofthe oil and water and the escape of the gas, and then show how theseveral parts are operated.

In the drawings, a is the tubing of the well or risingpipe, throughwhich the oil and water are raised. The flow-pipeb, which is curved at0, so as to form a trap to prevent any gas from passing out with the oiland water, is placed at a lower level than the branch gaspipe (I, whichcarries off the gas as it escapes through apertures n in the top of thegas-pipe 6, above the level of the oil and water in the tube a. The gasfrom the well may be conducted by the branch pipe (1 to a gas-holder andused for illuminating purposes or as fuel under the boilers of thesteam-engine. Thelowest section of the well-tubing a is screwed into theupper end of the pump-chamber or Working barrel f.

The gas-pipe 0 extends from the top of the well-tubing a to the box 9 ofthe check-valve h, being screwed at its lower extremity into thecheck-valve box g, which is inserted into the lower end of the lastsection of tubing a, just above the working chamber of the pump. Thecheck-valve h rests on a valve-seat, t', which is screwed into thecheck-valve box g. A short piece of gas-pipe, j, of such diameter as towork closely (like a telescope-slide) inside the main gas-pipe 0, passeslongitudinally through the center of the check-valve h, and also throughthe working valve 70, and is fastened to the top ring of theworking-valve box I, thus serving as a guide to the check-valve h andworking valve it, both of which slide on it. The working valve it rests,when closed, on a valve-seat, m, screwed up into the working-valve boxI, and incloses the leatherpacking-rin g 0. The working-valve box orpiston l is moved up and down in its stroke by means of two rods, 19 p,screwed into it and extending upward through the check-valve box g andoutside of the gas-pipe c, to the top of the well.

At the lower extremity of the pump-chamber f is seated the bottom valve,q, in a suitable valve-box, 1". On top of the valve q is a tubularprojection, s, forming a step or seat for the end of the rod t, whichrod extends upward in the center of the well through the gastubes 0 andj, leaving sufficient space around it in these tubes for the freepassage of the gas.

The mechanism by which the several parts of the pump are operated, asshown in Fig. 1,

is constructed as follows: The walking-beam w, by which the stroke ofthe piston-rods p is effected, is supported by and vibrates on astandard, u. It is connected to one extremity of a link, 0, the otherextremity of which is connected with the free end of the lifting-arm m,the center of the link being pivoted to the head of the piston-rods p p.The top of the rod 15, by which the bottom valve, q, is shut down,ispivoted to a horizontal lever, 31, which has its fulcrum in the standard2 at i. The lifting-arm no is also pivoted to the standard 2 at i. Fromthe lifting-arm m hangs a pendant, (1, consisting of two parallel rodsconnected by a pin, 0, at their lower end, or a single rod with a loop,the pin 0 resting against the face of a cam, a, so as at the proper timeto enter a notch or recess, a, in the cam, and either raise or depressit, as the lifting-arm m is raised or lowered by the vibration of thewalking-beam w. The lever r attached to the lower valve-rod, t, rests onthe top of the cam a, so that when on the upstroke of the pistonrods 12p the lifting-arm 0c is raised and the cam to also raised, the lever yis forced upward, elevating the valve-rod t; and as soon as thedownstroke of the piston-rods p 19 commences the cam a is turned down,which lowers the lever r or allows it to fall, when the valverod 13descends by its own weight on the lower valve, q, and closes it. The cama has its center of motion or hearing in a small standard, I).

It is important that the device for raising and lowering the valve-rodit should be so arranged in the manner described, or otherwise, as thatthe rod 75 shall be raised as soon as the upstroke of the piston of thepump commences, and be sustained until the downstroke begins, and thatit should be then immediately re leased and allowed to fall on the valveq.

Having thus described the construction of my improved pump, I willproceed to describe the effect produced by its operation.

On the upstroke of the piston l the lever 31 is raised, as beforestated, by the cam a, and thus the rod t is elevated more or less,according to the shape or stroke of the cam, so as to leave the lowervalve, q, free to rise, which it will do, not by atmospheric pressure inthe ordinary way, but by the upward force of the gas from the wellbelow.

In my pump, constructed as shown in the drawings, the gas-pipes beingopen at both ends, the raisingof the piston ldoes not create a vacuum,which is unnecessary for the reason just stated; but, if desired, avalve may be placed on the upper end of the gas-pipe, so as to make thepump work by atmospheric pressure, and the apertures 12 dispensed with.

On the rising of the piston l the gas rushes through the valve q, andfinds a free vent through the gas-pipes c and j, and the chamber of thepump, between the valves 70 and q, is filled with oil, or oil and water,from the well below, and at the same time the contents of the spacebetween the working valve is and check-valve h are lifted up by thevalve 70, and forced upward above the check-valve h.

When the downstroke of the piston 1 begins the cam a turns to allow therod tto drop upon and close the lower valve, q. Should the weight of therod 15 prove insufficient to counteract the forcepf the upward flow ofgas and oil, the rod 25 may be weighted by means of a poise suspended onan extension of the lever y. The piston and working valve 70 thendescend, and the check-valve h is closed by the weight of thesuperincumbent column of oil and water in the well-tube a, which is thusprevented from pressing down on the valve 70 or forcing the oil andwater up the gas-pipes c andj.

By the descent of the piston Z the contents of the pump-chamber betweenthe valves 76 and q pass above the working valve k, ready to be liftedabove the check-valve on the next upstroke of the piston. I

What I claim as my invention, and desire to secure by Letters Patent,is-

1. The detached rod t, in combination with the lower valve, q, for thepurpose of keeping the lower valve closed on the downstroke of thepiston.

2. The combination and arrangement of the lever y and valve-rod t withthe cam a and pendant d, for raising and lowering the valverod t, torelier'e the lower valve, q,.ot' its pressure when the upstroke begins,and hold it down on the commencement of the downstroke, substantially asdescribed.

3. The combination of the check-valve hand gas-pipej c with the workingvalve of a pump, constructed and arranged substantially as and for thepurposes hereinbefore described.

4. In its arrangement with the devices described in the third claim, thetrap c in the flow-pipe, to prevent the passage of gas in thatdirection, substantially as described.

In testimony whereof I, the said BENJAMIN CRAWFORD, have hereunto set myhand.

BENJ. CRAWFORD.

Witnesses W. BAKEWELL, ALLAN G. BAKEWELL.

